Operators of machines face the risk of injury by coming into contact with moving parts of the machine. For instance, if the hair or clothing of a machine operator were to become entangled with a moving part such as a rotating shaft, then the hair or clothing of the operator may quickly become quickly wrapped around the shaft and the operator can be quickly dragged towards and into contact with moving parts of the machine, which can give rise to very serious injuries. This risk exists during normal operation of the machine and whilst making maintenance inspections or adjustments.
To reduce the risk of injury to machine operators or maintenance workers, a machine may be fitted with guards which obstruct access to moving parts. This can present an inconvenience to machine operators or maintenance workers, as sometimes it is necessary to remove the guard to carry out routine inspections or maintenance. Unfortunately, it has been found that in practice some guards are sometimes not refitted after removal, and consequently the protection offered by the guard is then lost and the risk of injury during the future operation of the machine is increased.
Rotary pumps typically comprise a bearing housing and an impeller housing, with a driveshaft extending between the bearing housing and the impeller housing. An adjustable gland seal is provided at the region where the driveshaft enters the impeller housing. The function of the gland seal is to resist escape of pumping medium, such as a slurry or liquid, from the pump whilst allowing for rotation of the driveshaft which supports and drives an impeller located inside the impeller housing. The gland seal is often provided with its own pressurised water supply and some amount of leakage of water or other fluid is normal during operation of the pump.
The gland seal typically includes some type of packing material which becomes compacted or worn over time. This necessitates regular inspection of the rate of leakage from the gland seal and the making of regular adjustments of the degree of compression applied to the packing material which is typically effected by progressive manual tightening of nuts or bolts which hold a gland follower in compressed relation to the packing material.
There remains a need for improved guard arrangements for use in association with the region surrounding the driveshaft and gland seal of a rotary pump.